BOSTON (CBS) – One Boston Marathon bombing suspect is dead and the other – his brother – was taken into custody in Watertown Friday night.

Dzhokhar Tsarnaev, 19, was found hiding in a boat in the backyard of a home. The homeowner reported seeing blood on the wrap of the boat, and police quickly descended on the area. The suspect sustained unknown injuries during a gunfight with police early Friday morning.
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His brother, 26-year-old Tamerlan Tsarnaev, is the other suspect. He was killed by police overnight in Watertown. CBS News correspondent John Miller says Tamerlan threw a pressure cooker bomb at police before he was shot and killed.

The men are originally from Russia in the region near Chechnya.

SWAT teams searched dozens of Watertown homes Friday but did not find Tsarnaev.

He was captured and rushed to Beth Israel Deaconess Medical Center in Boston, where he died at 1:35 a.m. Doctors said he had gunshot wounds and a blast injury. The wounds were throughout the trunk of his body.

SUSPECT #2

Boston Police released a surveillance image of Dzhokhar around 4:20 a.m. Friday. He is the man with the white baseball hat in the FBI photos released Thursday in connection with the bombings probe.

Boston Marathon bombings suspect #2

“We believe this to be a terrorist,” Boston Police commissioner Ed Davis told reporters. “We believe this is a man who’s come here to kill people.”

HOW IT STARTED

The chaotic turn of events in the investigation began late Thursday night.

According to WBZ-TV Chief Correspondent Joe Shortsleeve, the brothers ambushed Collier, shot him five or six times and once in the head. Collier never drew his weapon. His gun was found in his holster. Five 9 mm shells were found at the scene. It is unclear what led up to the shooting.

Police originally believed the brothers may have held up a convenience store in the area, but later stated that was not the case.

Massachusetts State Police said the brothers did stop at a 7-11 to purchase gas. They spent the night in a Honda Civic (originally reported to be a CRV) and used it to carjack a Mercedes SUV in the area of Third Street in Cambridge. One of the brothers stayed with the carjacking victim for a few minutes and then let him go at a gas station on Memorial Drive. He was not injured.

Police said one brother drove away in the Civic, and the other one drove away in the Mercedes.

One then abandoned the Civic in Cambridge and joined up with his brother again in the Mercedes.

According to Shortsleeve, MBTA transit police intercepted the Mercedes in Cambridge and followed it.

Miller reported that Tamerlan Tsarnaev threw a bomb at police as he approached them and that’s when officers shot and killed him. This bomb is reported to be a pressure cooker bomb, the same that was used in the Boston Marathon attack. Miller says the lid of the pressure cooker came off before it exploded, so it was not as severe of a blast.

State Police say numerous pieces of evidence is being recovered from several Watertown scenes including evidence of homemade explosives, including pipe bombs and the pressure cooker, as well as more than 200 spent rounds.

BROTHER RUNS OVER BROTHER

Shortsleeve’s source said Dzhokhar Tsarnaev then jumped back in the Mercedes, drove over his brother’s body, threw bombs at police and crashed again. He ran off and that sparked the massive manhunt in Watertown.

Sources indicated to Shortsleeve the theory is the brothers were robbing people in order to get cash to escape the area.

It’s not clear why the brothers allegedly killed the MIT officer, but the theory is the brothers may have seen him on his cell phone and they thought he was calling them in.